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    <h1>
        <pre>
        siblings()所有同胞
        next()下一个同胞
        nextAll()
        nextUntil()
        prev()上一个同胞
        prevAll()
        prevUntil()
        </pre>
    </h1>
    <div>
        <h3>AAA</h3>
        <p>BBBB</p>
        <span>cccc</span>
        <b>DDDD</b>
        <s>ffff</s>
    </div>
    <ul>
        <li>
            <span>家用电器</span>
            <div class="item">家用电器</div>
        </li>
        <li>
            <span>手机/电脑/数码</span>
            <div class="item">手机/电脑/数码</div>
        </li>
        <li>
            <span>手机/电脑/数码</span>
            <div class="item">手机/电脑/数码</div>
        </li>
        <li>
            <span>办公</span>
            <div class="item">办公</div>
        </li>
    </ul>
    
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